"""
    kevrandom.py - Extra random functions.
    This file is part of EvoStumps.

    EvoStumps is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This software is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this software; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
"""

import math
import random
import logging

class KevRandom:
    def __init__(self):
        pass
        
    def laplacian(self):
        sample = math.log(random.random());
    	if random.random() < 0.5:
    		sample *= -1.0
    	return sample;